The invention relates to a device for detachable fastening of an embroidery frame on an embroidery frame support, and more particularly to such devices for an embroidery module in a program-controlled sewing or embroidering machine.
The connection between an embroidery frame and its support which has the drive apparatus for the embroidery frame, must be separable in order on the one hand to have the possibility of being able to fasten embroidery frames of various size and shape on the embroidery frame support, and on the other hand, to be able to lay the material to be embroidered, for example a fabric, outside the sewing machine into the embroidery frame, and to fasten it there.
From DE-GM 29 614 512, such a device for detachable fastening of an embroidery frame on the embroidery frame support of a program-controlled sewing or embroidering machine is known. In the embroidery frame support which is arranged in household sewing machines alongside the lower arm and is connected with this through coupling and latching devices, the drive means for movement of the embroidery frame attachments in the x and y direction is arranged. On the embroidery frame support, a holding angle of steel with upward-projecting retaining studs is provided for connecting or coupling the embroidery frame. On the embroidery frame, a guidance channel open downward is fastened, into which the vertical section of the holding angle is latchable with the retaining studs insertable from below, and latchable through two opposing movable locking slides. The sliding interlocks are guided lengthwise in the guidance channel and connected with two holding plates. The holding plates project beyond the guidance channel such that they can be grasped with two fingers of a hand and can be pressed against each other. Between the two locking slides, a spring is inserted which presses these apart when the spring is released, and thus pushes the outwardly directed ends under the retaining studs in the guidance channel. This known device makes it possible, in a simple manner and with the use of only one hand, to fasten the embroidery frame on the embroidery frame support or to remove it therefrom. It has, however, the disadvantage that the embroidery frame, due to the vertically operating latching in the x and y direction, cannot be held sufficiently free of play and in this way, the reproducibility of the embroidered pattern cannot be guaranteed in every case.
From DE-GM 29612102, a device for the automatic identification of the size and construction of an embroidery frame on a sewing or an embroidering machine with program-controlled embroidering device is furthermore known. This device makes it possible for the control unit of the sewing machine to recognize the embroidery frame directly connected with the embroidery frame support and therewith to utilize completely the surface available for embroidering within the embroidery frame. As a means of identification, on the embroidery frame, in the region below the guidance channel, corresponding means of identification, for example, coding prongs, are provided. The identification means are joined fast with the coupling and latching apparatus in the known device, and for this reason only allow a recognition of the respective embroidery frame which is connected fast with the latching apparatus. If there is a possibility on the embroidery frame of connecting this at various points with the embroidery frame support, then in the known manner, no identification of the fastening point can take place on the corresponding embroidery frame.
The object of the present invention is to create a device for detachable fastening of an embroidery frame which not only makes it possible to join the embroidery frame with the embroidery frame support, but to lock the embroidery frame in at different places with reference to the embroidery frame support in order to be able, by successively using correspondingly larger embroidery frames, to embroider basically larger embroidering fields.
A further object is to provide, after fastening the embroidery frame on the embroidery frame support, the possibility of making the place of attachment on the respective embroidery frame type determinable by the control unit or appropriate sensors.
This object is accomplished by a device in accordance with the invention by providing a drive connected to an embroidery frame support with an embroidery frame holding plate attached thereupon. A retaining and latching element is installed on the embroidery frame with two movable sliding interlocks with spring-loaded grips. The sliding interlocks each engage with one latching hook on correspondingly constructed latching surfaces in recesses located in plates on the embroidery frame holding plate. The retaining element is mounted movable along a guide rail on the embroidery frame, and code sections and latching slots are positioned on the guide rail or on the embroidery frame.
With the device of the invention, a play-free latching of the embroidery frame on the embroidery frame support is possible, and at the same time, with one and the same latching and coupling device, the embroidery frame can not only be joined with the embroidery frame support, but also to move this without the prior detachment from the embroidery frame support, latching it again, and identifying the latching site through the control unit. By pressing together both holding buttons, the embroidery frame can consequently be lifted from the embroidery frame support again as previously, or it can be slid along a guide track fastened to the embroidery frame and fixed at a suitable position, and the fastening site on the embroidery frame can be recognized by the guide unit of the machine. Sliding the embroidery frame in relation to the embroidery frame support takes place through briefly pressing the holding buttons together and subsequent lateral sliding of the embroidery frame. The locking in into the adjacent operating position then takes place automatically. When locking in, additionally a play-free clamping of the embroidery frame with the embroidery frame support takes place without further interventions by the operator being necessary.